Automatic engine stopping means



Aug. 1, 1933. M. M.-HANCOCK 1,920,694

AUTOMATIC ENGINE STOPPING MEANS Filed Feb. 12. 1951 Patented Aug. 1, 1933 Application Februaryl2,1 931. SerialNo.515,324

1Claim.' (o1.1'23 -'-1:4615)' f The invention aimsto provide new and improved means for automatically stopping an internal combustion engine in case the quantity oflubricatingoiltherein has diminished to a 5 dangerous degree, from any cause, and it aims further to provide such a relation of elements.

. that no. manual operations are necessary torecondition the ignition circuit for motor opera tion, after replenishing the oil supply. 1

310 A still further object is the provision of means which positively breaks the ignition circuit to stop the motor when the supply of oil is low.

With the foregoing inview, the invention resides in the novel subject matter hereinafter described and claimed, description being accomplished by reference to the accompanying drawing, in which the figure is a diagrammatic sectional view showing the invention.

While the invention is intended primarilyfor use upon automobiles, it is adaptable also to stationary internal combustion engines. ,A conventional battery 1 is shown for the ignition circuit of the engine, said circuit embodying,,in the present disclosure, the wiring 2, 3, 4, and 5, the

' conventional manually controlled ignition switch 6, and a second normally closed switch 7. I have shown this switch 7 within an insulating housing 8 and pivoted at' 9 to a binding post 10 with which the wire 3 is connected, said switch '7 being normally held by a spring 11 against a contact 12 on the inner end of a second binding post 13, the latter being connected with the wire 4.

An electro-magnet 14 is mounted within the casing 8 for opening the switch '7, thereby positively breaking the ignition circuit and stopping the motor, when the lubricating oil in said motor has diminished to a dangerous extent. A circuit for the electro-magnet 14 is provided, said circuit being preferably shunted from the ignition cir- Y cuit. This shunt circuit embodies switch 6 but not switch '7, and it also includes a normally open, self-closing switch 15 which is co-operable with two contacts 16 and 1'7, and pressure-held means suchas a plunger 18 subjected to the the motor, is employed for normally holding. said switch 15 against closing. Coil springs 19 are illustrated for 'moving'theswitch 15 into engagement with the contacts 16 and. 17, when decrease of pressure in the line 19 allows the plunger 18*to move inwardly. The wiring of the shunt circuit may well be as illustrated, A wire 20 is shownleading'from the binding post 10 tothe e1ectro-magnet-14, and wiring ,21 leads from said electro-magnet to a binding post 22 pressure within the oil-circulating line 19' of carrying the contact 17. i A wire 23 extends to the wire 5 from a binding post-24' which carries the contact 16.

7 As long as the motor is operating andicontains,

a proper quantity of lubricatingbil, switch '7 remains closed, switch 15 remains open, and' 'the current-forthe ignition circuit travels as shown by the full line arrows. As "soon as the oil pres-. sure recedes sufiiciently from any cause however,

the springs 19 move the switch 15 into engage- 5 rnent with the contacts 16 and 17, whereupon the current travels as shown by the dottedarrows, said current energizing the 'electromagnet 14 and causing the latter to open the switch 7, there" by positively breaking the ignition circuit and stoppingthe motor. a

I preferably provide ania dditio'nal shunt circuit for a tell-tale light25 disposed at any desired, conspicuous location, said shunt circuit being branched from the circuit of. the electro magnet 14 and embodying the switch 6. In the I present showing, a Wire 26 connects one terminal.

of this lightwith the. wire 3 and another wire 27 connects the other terminal of saidlight with the wire .21. Thus, as soon as theelectro-magnet'M g is energizedto stop the motor, the tell-talelight 25 is illuminated, notifying the operator that the motor has stopped from either lack of oil or lack of proper oil pressure. Consequently,"theignition switch 6 is opened and the trouble rectifiedlAs s soon as switch 6 is opened, the electro-magnet "14 becomes de-energized and consequently the I switch 7 is again closedby-the spring '11, the switch 15 remaining at that time closed. 1 Opening-of switch-6 also extinguishes the tell-tale 25.

,When the motor is to be re-started, the ignition" switch 6 is first,closed,,and asthe switch 15 is then also closed-the electro-magnet 14 will be. energized and'will open the switch '7. Even though ,this switch is in the ignitioncircuit, it will not interfere with re'-startin'g of the motor, for as soon as said motor is turned over with theusual.

self-starteror even by hand, the oil pumpfagain buildsrup pressure and opensthe switch 15, immediately tie-energizing the electro-magnet 14 and causing the switch 7 to again close, completing the ignition circuit 7 Even if there be proper supply of lubricating oil in. the motor, the pressure will'g'radually leak from the oil line 19' when the motor is stopped by cutting off the ignition switch 6. Hence, the 7 switch 15 will eventually close. It thus follows that when the switch 6 is again closed .to start the motor, the e1ectro-magnet'14 is energized andis turned over by the starter. or otherwise however, the oil pressure again builds up, opening I the switch and causing the electro-magnet 14 to become de-energized, sothat the switch 7 may reclose, completing the ignition circuit.

It will be seen that novel and inexpensive provision has been made for carrying out the objects of theinvention. Particular attention is invited to the fact'that the ignition circuit is positively broken to stop the motor. Attention is also invited to the fact that no manual operations are necessary to restore the ignition circuit to 0perative condition after the switch 15 has closed from any cause, the re-closing of said ignition motor,

circuit when it is desired to re-startthe being carried out automatically.

Whilethe wiring disclosed may, be followed if desired, any other adequate wiring 'could of course be employed, and it is not essential that I claim: V

In combination, an engine having an ignition circuit embodying a manually-actuated ignition switch and a second ignition switch of self-closing form, the latter having an electro-magnet for opening it; a circuit 'for said electro-magnet branched from said ignition circuit and embodying said manually-actuated ignition switch but not said secondignition switch, said circuit of said electro magnet embodying a second self closing switch, means controlled by the lubricating oil of the engine for holding said second self.-

.closing switch open, a tell-tale, and a circuit for said tell-tale branched from saidelectro-magnet circuit and embodying said manually-actuated ignition switch; whereby upon closing said manually-actuated switchthe engine may be op- 1 erated untildiminis'hed oil permits closing of said a second self-closing switch and the latter efiects;

simultaneous opening of I said second ignition switch and operation of said tell-taleand whereby opening of said manually-actuated ignition switch will again cause closing of said second ignitionswitch and discontinuance of said tell- 7 tale, thereby discontinuing currentconsumption.

MANLEY- MARTINHANCOCK.

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